Investigating Offspring Mental Health Outcomes Associated with Maternal Prenatal Alcohol Use

Abstract

Maternal prenatal alcohol use is associated with a range of harms in offspring, particularly for high levels of alcohol exposure. Yet prenatal alcohol exposure (PAE) is still common, particularly at low levels of exposure. The effects of low to moderate alcohol exposure during pregnancy are variable with complex aetiologies and often studied within younger offspring age groups. In the studies reported in this thesis, I investigated if PAE was associated with offspring mental health, particularly for internalising disorders within late adolescence, assessing if any associations shown from previous literature for younger offspring ages may persist into adulthood.
This thesis applied different methods to explore the associations between maternal alcohol use in pregnancy and offspring mental health. I conducted a systematic review exploring the association between PAE and offspring mental health. I then applied a negative control analyses within a longitudinal birth cohort to investigate the association between PAE and offspring depression. Next, I explored the potential environmental influences of parental drinking after birth on offspring mental health. I then used a Phenome Wide Association Study (PheWAS) to investigate the effect of maternal and offspring genetic variants for increased alcohol use on a wide range of offspring mental health phenotypes across the phenome. Lastly, I used repeated measures to investigate associations between PAE and offspring trajectories of depression and latent classes of conduct disorder.
I found evidence of an association between increased maternal prenatal alcohol use and offspring mental health problems that suggested a causal effect. However, all associations were attenuated or removed entirely after adjustment for potential confounders, which may be causing a large part of the associations found. The findings of PAE still showing associations with mental health outcomes even during late adolescence, would suggest the associations previously seen within the younger developmental ages may indeed also be shown until early adulthood. Overall this thesis highlights the many problems encountered when investigating this topic, meaning inferring the causal nature of effect is problematic.

Date of Award	23 Jan 2020
Original language	English
Awarding Institution	University of Bristol
Supervisor	Marcus R Munafo (Supervisor), Nicholas John Timpson (Supervisor) & Luisa Zuccolo (Supervisor)